Safety evaluation of certain food additives - ipcs inchem

180 POLYDIMETHYLSILOXANE (addendum)
did not reveal any significant differences between the two materials. However, the
reports of the toxicological studies on which the ADI was established at the
eighteenth meeting did not refer to any ocular effects, and it is unclear whether
ophthalmological examinations were conducted. Conversely, in all the more recent
short- and long-term studies of toxicity with PDMS reviewed at the present meeting,
dose-dependent increases in the incidence and severity of ocular lesions were
consistently observed after oral dosing both in the diet and by gavage. It was stated
in the study reports that this seems to be a local irritant effect; however, it is unclear
whether the eye might have been exposed topically to PDMS at a level causing
irritation, particularly after administration by gavage. Furthermore, the Committee
was aware that studies of ocular irritation conducted in relation to cosmetic use
resulted in PDMS being classified as a mild to minimal irritant, but the material tested
may have differed from that used in the studies in which PDMS was administered
orally. The mechanism by which the ocular lesions arose is therefore unclear,
although the lack of absorption of PDMS indicates that it is unlikely to be a direct
systemic effect. Consequently, the relevance of the ocular lesions for food use of
PDMS could not be determined.
The previously established ADI of 0–1.5 mg/kg bw was withdrawn. Using an
additional safety factor of 2, the Committee established a temporary ADI of 0–0.8
mg/kg bw for PDMS, pending the results of studies to elucidate the mechanism and
relevance of the ocular toxicity and provision of data on actual use levels in foods.
The temporary ADI applies to PDMS that meets the revised specifications prepared
at the present meeting. The temporary ADI will be withdrawn if the required data
are not provided before the end of 2010.
6. REFERENCES
Codex Alimentarius Commission (2008) Codex General Standard for Food Additives (GSFA)
online database. Rome, Italy, Food and Agriculture Organization of the United Nations
(http://www.codexalimentarius.net/gsfaonline/index.html).
European Centre for Ecotoxicology and Toxicology of Chemicals (1994) Linear
polydimethylsiloxanes (CAS No. 63148-62-9). Brussels, Belgium, European Centre for
Ecotoxicology and Toxicology of Chemicals, Joint Assessment of Commodity Chemicals,
September (JACC Report No. 26).
European Food Safety Authority (2008) Guidance document for the use of the Concise
European Food Consumption Database in exposure assessment. Parma, Italy, European
Food Safety Authority, 17 March (EFSA/DATEX/2008/1; http://www.efsa.europa.
eu/cs/BlobServer/General/Coincise_database_guidance_document_and_annexes,3.pdf?
ssbinary=true).
Food Standards Australia New Zealand (2008) Submission to WHO in response to call for
data.
Hansen, S.C. (1979) Conditions for use of food additives based on a budget method for an
acceptable daily intake. J. Food Prot., 42, 429–434.
Lukasiak, J. & Falkiewicz, B. (2000) A mistake in the JECFA recommendations on
polydimethylsiloxane (PDMS). Food Addit. Contam., 17(11), 945–946.
Meeks, R., Jean, P., Mertens, J., Regan, K., Crissman, J. & Plotzke, K. (2005) Chronic toxicity
and oncogenicity study of polydimethylsiloxane (PDMS) 10 cSt fluid in F344 rats. Toxicol.
Sci., 84(1–S), 308.